Grinding mill



Nov. 6 1923., 4 1,473,341

W. A. GIBSON ET AL GRINDING MILL Filed Nov. 16. 1921 2 Sheets-Sheet 1 inventors William A. Gibson Charles E. Needham Mtys,

Nov. 6 1923. 7 1,413,341

W. A. GIBSON ET AL GRINDING MILL Fi led Nov. 16. 1921 2 Sheets-Sheet 2 Fig. 2.

L I 7 as lnvemors.

Wiiliom A. Gibson Charles E. Needhum b -mwkw res iii

Patented Nov. 6, 1923.

UNITED STATES PATENTOFFICE.

V/ILLIAM A. GIBSON AND OHARLES E. NEEDHAM, OF ALLENT OWN, PENNSYLVANIA,

ASSIGNOIELS TO BRADLEY PULVERIZER COMPANY, OF BOSTON, MASSACHUSETTS,

A CORPORATION OF MAINE.

GRINDING ILL.

. Application filed N'ovember'lS, 1921. Serial No. 515,509.

1904, and No. 1,175,436, granted March 14:,

1916. In this type of grinding mill, the material to be ground is crushed against an annular grinding ring by the centrifugal action of a plurality of rolls which are carried by shafts, which are pivotally mounted on a carrier, which is rotated by a central vertical roll actuating shaft.

In this type of mill as heretofore .con-

structed the vertical roll actuating shaft has been directly driven by a large pulley secured to the upper portion of said shaft. This has required the use of a belt, the leads of which engaging the pulley are vertical if driven from a vertical shaft, or are twisted if driven from a horizontal shaft.

One of the objects of the present'invention is to provide an improved driving' mechanism through which power may be transmitted by suitable gearing to the vertical roll actuating shaft from a horizontal driving shaft, which may be rotated either by a horizontal belt. or may be directly connected conveniently to a suitable motor.

A. 'iturther object of the invention is to provide a frame having a single supporting girder for sustaining the weight of the rotating parts and providing a journal for the vertical roll actuatiiig'shaft.

Another object of the invention consists in providing a single supporting girder of this type with suitable bearings for a driving shaft located at right angles to the axis of the vertical roll actuating shaft.

A further object of the invention is to provide a bevel gear drive forsaid vertical roll actuating shaft," in which means are is. a specification, like 'char-' provided for maintaining the proper lubrication of the gears.

A further object of the invention consists in providing a novel bearing construction for the driving mechanism which supports the roll actuating shaft.

A further object of the invention is to provide an overhead drivefor a grinding mill of this character which will be more accessible for purposes of repair or replacement than in former constructions.

Other objects and features of the inven tion will more fully appear from the fol lowing description and the accompanying drawings and will be pointed out in the claims.

A preferred embodiment of our invention is illustrated in the accompanying drawings as applied to a centrifugal grinding mill of the type generally illustrated in the Griitinpatents above mentioned, and inasmuch as improvements to which this invention relates are not concerned with the grinding rolls which are operated by the vertical roll actuating shaft, this well known mechanism has not been illustrated in the accompanying drawings. It will, however, be understood that any usual type of centrifugal grinding mechanism operable from the vertical roll actuating shaft may be em ployed' so far as the present invention is concerned.

In the drawings:

Fig. 1 is a Side. elevation of a centrifugal grinding mill, certainparts of the upper POIiJlOllOf the" frame 111 the driving mechanism being illustrated in vertical section; Fig; 2 is an end elevation of the grinding mill shown in, Fig; 1,, the driving shaft b'eing shown in section, the pulley and outer bearing being on1itted;'

Fig. 3 is a vertical sectional view through the central portion of the upper girder of the machine. lllustrated in Fig. 1, showlng the hub of the driving mechanism which supports the vertical roll actuating shaft in elevation, and illustrating the bearings and lubricating mechanism forming a part of the invention.

The centrifugal grinding machine to which the invention is applied comprises a base portion -1, whicheontains the grind .Jortin the su Jerstructure of the mill which carries the vertical roll actuatingshaft. and the carrier which supports the centrifugal actuated rolls which cooperate with the grinding ring. The present invention. comprises. a novel frame, which consists in pairs of preferably A-shaped standards 2 and braces 23, which are firmly secured at their lower ends between suitable lugs extending upwardly from the base 1, and at their upper ends. are securedto and support saddles, l, which carry a cross girder which sustains the rotating parts of the mill Oneof the principal features of the in vention relates to the design of the frame construction, in which the central girder and its seat are so formed as'to be readily assembled and accurately adjustedto position properly. the bearing for the-vertical rolllactuating shaft This is accomplished inthe preferred embodiment of the invention by providing the saddles which are sup-portedonthe standards, with concave, preferably semi-cylindrical, sockets 5, which areadapted to receive the turned end sections (S 7 of the cross girder 8. By reason of this construction, the ends of the cross girder 8 can be readily dropped into the sockets 5 in saidsaddles, and 'securedtherein by suitable fastenings such as bolts 9, extending-down through the lower portions of said end sections and through the saddles.

The irder desirabl is in the form of a slightly arched beam having a central, preferably. enlarged, annular portion 10, with members 11 and 12 extending radially therefrom and terminating inthe horizontal turnediextensions 6'? above described. he central portion 10 of the upper girder is provided with an aperture 13, through which the central roll actuating shaft extends, and in whichit is carried by the hub of the driving mechanism, which is journalled in said aperture ina manner which will be hereinafter fully explained.

The member 12 ofthe upper girder 8 desirably is soconstrncted' as to containsupports for the bearings ofthe driving shaft, and also preferably to provice a lubricant well for a pinion on said. driving shaft which drives a suitable gear for rotating the roll actuating shaft. In th construc tion illustrated, the member 12 of theuppcr girder S is provided withbearing receiving recesses let and 15 extending lengthwise of the1ne1nberrl2, in which thebearings 16 and 17 of. a drivingshaft; 18* are mounted. The: driving; shaft 18 may; beidriven convenientl 7 through a. pulley l5) keyed upon said driving shaft.

Inasmuchas grinding mills ofthis character. are; usually very large andzrequirea large; amount; of: pow-er;- a supplementalrem ss-1 bearing 20 desirably provided for the free end of the driving shaft. Finch a hearing may be conveniently supported upon a separate frame or pillar 21.

The. vertical roll actuating shaft may b con ve icntly driven from the driving shaft through a pair Or train of gears of well known type. As illustrated. licreirn the bevelled pinion 22, which is lieyed to the driving shaft 16 engages the teeth of an annular bevelled ring 23, forming part of a. gear 2%, which is secured to and supports the roll actuating shaft, as will be hereinafter more fully explained.

Preferably the portion 12 of the girder b is provided witha well 25, which forms an oil receptacle and also serves to enclose the lower portion of the pinion 3y reason of this construction, the lower portion ofthe gear is always caused to run in oil, and the oil which is carried up by it will lubricate effectively the teeth 28 of the gear 2%. A drip pan 26 preferably formed i two half sections to embrace the, rotating mechanism, lies below the gear 2st, and is provided with an inclined bottom surface 26*, which delivers the excess of oil'which drips fromthe gear back to the oil well A- suitable cover may be dctachably superimposed upon the drip pan, or other supporting member, to form with the drip pan a chamber enclosing the gears and protecting them from dust and other foreign materials. I

A thrust bearing 27 is desirably introduced between the end of the bevelled pinion 22 and the wallxof the well 25, in order to prevent endwise movement of the shaft due to the component of force acting in the direction of the axis of the driving shaft, resulting from th thrust between the teeth of the pinion 22 and those of the bevelled ring 23, which forms a part of the gear 2st.

he gear 2% is provided with a hub which has an extension 28 which extends into the aperture 13 in the girder S, and preferably projects a short distance through the lower end of said aperture.

The vertical roll actuating shaft extends upwardiy through the centre of the gear hub, and supported thereupon preferably by a wedge-shaped split nut 29 which seated upon a complementary supporting member 30, which engages the upper end of the hub. The hub is upported upon antifriction bearings carried by the cross-gird er 8.

In the preferred; construction illustrated, an annular cup shaped member 31 is seated upon the upper end ofithe central portion 10' of the girder 8. This cup shaped member 31 1 provlded. with a preferably spherically concave scat-32 for an aligning washer 3S,

thenppentiat surface of \vhichsupportsthe- Cit lll-i lll) lower member 34 of a ball bearing. The

upper section 35 of the ball bearing is seated in a groove in the gear hub 28,-and supports the gear, and with it the vertical roll actuating shaft.

The cup shaped member 31 is so formed as to extend upwardly and, surround the outer wall 36 of the groove in which the upper section 35 of the thrust bearing is seated. Thus the cup shaped member 31 provides a chamber to receive the oil which is fed into the thrust bearing in a manner hereinafter to be described, and also serves to exclude dust from the bearing for the vertical roll actuating shaft.

A bronze bushing 37 desirably is interposed between the hub extension 28 and the wall of the aperture 13, and extends from near the lower end of the hub extension upwardly, preferably to the level of the ball bearing which sustains the gear 24.

, The lower end of the hub extension 28 projects below the central portion 10 of the transverse upper girder 8, and preferably is provided with an annular groove 38, which is engaged by a flange upon a sectional collar 89, which is clamped upon the lower end of said gear hub extension by a sleeve 40, which may be shrunk or otherwise clamped upon said collar. construction the extension 28 of the hub is, in effect, provided with a flange underlying thecentral portion 10 of the upper girder 8 end of thehub extension is enclosed in anoil chamber from which the oil is delivered by centrifugal force to the bearing and caused to creep up along the outer surface of the hub extension to the supporting thrust bearing, whence it is delivered into the cup shaped receptacle 31 and returned through a suitable duct into the oil chamber; As illustrated herein a receptacle 41 .is secured to the under face of the central. portion 10 of the girder 8 and is provided with a wall 42 which extends upwardly into a recess in the inner wall of the hub and closely adjacent to the shaft. This recess or chamber is of annular form and provided with an upwardly flaring outer wall 48,

through the upper portion of which ports 44 extend to the bearing, so that oil may be delivered to the bearing between the periphery of the hub extension and the bushing 37. By reason of the fact that this hub extension projects into the 'oil lIl-tlle oil By reason of this chamber 41, the centrifugal force of the rotating hub extension will cause the oil to creep up. along the upwardly flaring wall of the recess and thence through the port or ports 44.

A plurality preferably three ports, are

the oil entering them to ascend along the inner wall of the bushing 37. The oil will, therefore, be carried up between the hub and its bushing until discharged over the top of the bushlng 37 into the receptacle 31, from which it is conducted through a suit able duct 45 back tothe oil chamber 41. The duct 45 may be either formed by grooving the outer wall of the bronze bushing vertically, or by grooving or boring vertically through the central portion 10 of the cross girder. By reason of this construction a continuous circulation of oil may be maintained through the bearing, thus insuring proper lubrication of the hearing.

-The cup shaped member 31 which encloses the thrust bearing, and the receptacle 41 which underlies the lower end of the bearing, effectively exclude dust from the bearing, and also prevent any dripping of the oil into the material which is being pulverized. This is very important as it is desirable to keep the product free from any oil.

By reason of the present invention the parts of a large and heavy grinding mill have been greatly simplified, and so designed that they can be readily and accurately assembled, and can be driven from any usual system of power transmission.

The special construction of the girder with its bearings for the counter-shaft and turned ends adapted to seat in the complementary sockets in the saddles of the frame, likewise is of great importance as it enables the machine to be assembled more easily and more accurately, and also does away with a considerable amount of the superstructure heretofore employed in mills ofthis type.

Byreason of the overhead arrangement of the gearing the gears the driving shaft, and the bushings for all the bearings are ren (lei-ed easily accessible and may be readily .removed or replaced when worn without dismantling the grinding mechanism.

It willbe understood that the preferred embodiment of the invention disclosed herebe made within the spirit and scope of the following claims. 7

Having thus described theinventlon, what W8 claim as new, and desire tosecu-re by. Letters Patent, 15:

1. In a,ce1 itrifugal grinding millhaving a grinding chamber, avertical roll actuating shaft, :1 frame comprising standards located on opposite sides of'saidigrinding chamber having girder receiving saddles, a girder having an aperture for saidroll actuating shaft. and sections complementary to said saddles adapted to be seated therein, and

{.{llClC-Zr sections means for securing said rigidly to said saddles.

2. In a centrifugal grinding mill having a grinding chamber a vertical roll actuating shaft, a frame comprising standards located on oppositesides of said grinding chamber, girder receiving saddles carried bysaid standards, having semi-cylindrical sockets,

a girder having an aperturefor saidroll' .actua'ting shaft and sections complementary to the girder receiving soeltets, and means for securing said, girder sections rigidly to sa d saddles.

In a centrifugal grinding millhav-ing a grinding chamber a vertical roll actuating shaft, .1 frame comprisingstandards located girder receiving saddles carried by said standards, a. girder. having an. apertured portion providing a journalfor saidvertical actuating shaft, members extending. radially therefromhaving end sections complementary to said saddles and.alignedrecesses for bearings in one of said radially extending.

members, and a Wellintermediate of ther cesses for said bearings.

5. A glrder for centrifugal grinding mills comprising a substantially central portion,

having an aperture to receive a bearingfor a roll actuating shaft and members extending radially from saidcentral portionhaving c;\"liudrical end portions, recesses for bearings in one ofsaid members extending in radial. relation to the axisof said aperture, and a. well. intermediate of said re cesses.

6.111 11 centrifugal grinding mill. having a vertical. roll act-uatingishaft, a frame: comprising standards having saddles, provided with. se1ni cylmdr1cal sockets and a girder havi mg a substantially. central. portion pro vided with an aperture for sa d rollactuatg, ha udmembera extend ng. edla ly from saidcentral portion havingcylindrical.

end portions mountedin the. sockets in said standards, a driving shaft'mounted in bearings carri-cdby one of said radially extending girder members and extending length- Wise. thereof, a pinionon said driving shaft anda gear on said vertical roll actuating shaft engaging saidpinion.

7. In acentrifugal grinding mill having a grinding chamber a vertical roll actuating shaft, a frame. comprising standards located on diametrically opposite sides of said grinding chamber and a girder having a substantially-central portion provided with an aperture for said roll actuating shaft, members extending; radially from said central portion mounted on said standards, bearingreceiving recesses. in one of said radially extending girder members extendinglength vise thereof, bearings in said recesses, a driving shaft mounted in .said .loearings, abevelled pinionon saiddriving shaft intermediate of said bearings, and a bevelled gear onsaidroll actuating shaft engaging said pinion.

S. In a centrifugal grinding mill having a grinding chamber avertical roll actuating shaft, a frame comprising standards located on diametrically opposite sides ofsaid grinding chamber, and'a girder having a substantially central portion provided with an aperture for said rollfactuating shaft, members extending radially from said central portion mountedonsaid standards, bearing receiving recessesin one of saidradially extending girder members extending-lengthwise thereof, bearingsin saidrecesses, a driving shaft mountedin saidbearings, a bevelled pinion on said driving shaft. intermediate of said bearings, abevellcd gear on said rollactuat ing shaft engaging said pinion, and an antifriction thrust bearing acting upon said driving shaft to prevent endivise. movement thereof.

9. In; a. centrifugal grinding mill having a grinding member avertical roll actuating shaft, aframe comprising standards located on opposite sides of said-grinding chamber, a girder having a substantially central portionprovided with an. aperture for said roll actuating shaft and members extending radially, from said central portion mounted on said standards, bearing receiving rccessesin one of said radially extending girder menihers. extending lengthwise thereof, and a.

well in said. member intermediate of said bearing recesses forming anoil,receptacle, bear ngsnr, said bear ng recesses, a driving shaft mounted 111 said bearing.

10: In a centrifugalgrinding mill having a grind ng cha nbena vertical rollactnat ng a beveled 131111911 011; sa d driving shaft part ally en shaft, a frame comprising standards located on opposite sides of said grinding chamber, a girder having a substantially central portion provided with an aperture for said roll actuating shaft and members extending radially from said central portion mounted on said strandards, bearing receiving recesses in one of said radially extending girder members extending lengthwise thereof, a well in said member intermediate of said bearing recesses, forming an oil receptacle, hearings in said bearing recesses, a driving shaft mounted in said bearings having a beveled pinion partially enclosed in said well, a beveled gear on said roll actuating shaft engaging said pinion, whereby the r0 tation of the pinion in the said oil receptacle will lubricate said pinion and the teeth of said gear, and a drip pan underlying said gear, having means for returning the oil deposited therein to said well.

11. In a centrifugal grinding mill having a vertical roll actuating shaft, a frame COII1- prising an upper supporting girder having an aperture therethrough for said roll actuating shaft, driving means supporting said shaft, having a hub embracing said shaft journalled in said aperture having its end portion projecting downwardly through said girder and an anti-friction thrust bearing, mounted on said girder, supporting said driving means.

12. In a centrifugal grinding mill having a vertical roll actuating shaft, a frame comprising an upper supporting girder having an aperture therethrough for said roll actuating shaft, drivin means supporting said shaft, having a hue embracing said shaft j ournalled in said aperture, an anti-friction thrust bearing, mounted on said girder, supporting said driving means, and co-operating flanges on said girder and gear forming an'oil chamber for said thrust bearing and acting to exclude dust therefrom.

13. I11 a centrifugal grinding mill having a vertical roll actuating shaft, a frame comprising an upper supporting girder having an aperture therethrough for said roll actuating shaft, a driving means supporting said shaft, having a hub journalled in said aperture and projecting therethrough, and a retainin collar on the projecting end of said hub adapted to prevent upward movement of said hub in its journal.

14. In a centrifugal grinding mill having a vertical roll actuating shaft, a frame comprising an upper supporting girder having an aperture therethrough for said roll actuating shaft, a driving means supporting said shaft, having a hub j ournalled in said aperture and projecting therethrough, an annular recess in the projecting end of said hub, a split collar having a flange engaging said recess, and a clamping sleeve surrounding said collar.

In testimony whereof, We have signed our names to this specification.

WILLIAM A. GIBSON. I CHARLES E. NVEEDHAM. 

